Share

This mite’s method of hitchhiking is not recommended

If you’re a mite looking to travel, you could do worse than being swallowed by a slug. These spherical arachnids (pictured), most shorter than a millimeter, can trek up to 4 meters in the belly of a gastropod—about 2000 times farther than they can get on their own, according to a new study.

To make the find, researchers collected slugs and snails from a forest in Germany and examined their feces for live and dead mites. Then, they determined how well mites can survive digestion by feeding a known number to slugs and counting how many emerged alive in the feces. Finally, they let slugs defecate on sterilized soil without mites and checked the soil for mite populations 3 weeks later.

Thirty-one out of 42 slugs, and seven out of 15 snails swallowed mites. Their combined feces contained at least 36 species of mites, and more than two-thirds of them were alive. Various other organisms also popped up alive in the mollusk feces, including springtails, ciliates, nematodes, mosses, and plant seeds.